Anode supply system



p 1934- s. TARZIAN ANODE SUPPLY SYSTEM Filed Sept. 13, 1933 INVEN TOR.

A TTORNEY Patented Sept. 4, 1934 UNITED STATES PATENT? OFFICE 1,972,279 AN ODE SUPPLY SYS Sarkes 'I'arzian, Bryn Atwater Kent Manufacturing Company, Philadelphia, Pa., a corporation of Pennsylvania Application September 13, 1933, Serial No. 689,302 9 Claims. (Cl. 250-27) My invention relates to systems for supplying.

poled in connecting to a direct current source; or 7 it, with the switch in position for use with alterhating current, it is connected to a direct current source.

. Further, in accordance with my invention, in changing over to direct current operation, the

filter system is modified to reduce the voltage drop therein to offset the lack of voltage doubling.

My invention further resides in the features of combination and arrangement hereinafter described and claimed. I

For an understanding or my invention refer ence is to be had to the accompanying drawing in which:

Figure 1 illustrates diagrammatically an anode power supply suited for use with either alternating or direct current;

Figs. 2 and 3 illustrate the circuit connections of the system-of Fig. 1 as used for alternating and direct current sources, respectively.

Referring to Fig. 1, the system comprises a full source of supply.

The rectifier consists of anode a and cathode c which form one with the heaters h2 h4 of the tubes .V, V1, V2,

etc., of the radio receiver whose anode current is to be supplied by the system.

When the switch 1 is thrown to the left to fit the system for operation from an alternating curode a1 and the output terminal B. The voltage drop in the speaker winding may be used for biasing the grids of any one or more of the tubes V, V1, etc., and if the total voltage drop is too high, the tapped as at T for the gridto' the art. To give a specific example, the rectifier FW may be a rectifier tube of the type 25Z5, having low internal impedance. With the supply conductors 2, 3 connected to alternating current source of volts, the voltage across each of the condensers will be approximately volts, and assuming that the resistance of the field winding S is about 2500 ohms, and the load current of the receiver about 40 milliamperes, the output'voltage across the condenser C2 is about volts. The tap T may be at. such point that the drop of potential across the section s of the speaker is about 15 volts, which is suitable for grid-biasing purposes. It, with the switch in the AC position, affording the connections in Fig. 2, the supply conductors 2, 3 are pluggedinto a 110-volt direct current source, no injury will result since the condenser C is -in series with the source and no rectified current is available. A direct current path could be provided by short-circuiting condenser C, but there are two iserious objections to this simple expedient. If the supply conductor 2 were connected to the positive pole of the source or line LL, the circuit would function, but at low efiiciency, because of the large voltage drop across the speaker field S. On the other hand, if the supply conductors 2 and 3 are connected to the negative and positive terminals, respectively, of the direct current supply source, heavy current will fiow within the tube from anode al to cathode c1, which are now connected directly across the line; and since the tube is of low impedance, 11

it would be destroyed by the excessive current fiow. i

In accordance with my invention, voltage doubling is effected by the circuit shown in Fig.2 when are connected to the source properly, the current flows from the anode ato the cathode c to the output conductor 4. The current returns'from the external circuit through the negative conductor to the supply conductor 3. If, on the other hand, supply conductors 2, 3 are improperly poled,- so that the anode a-is negative, there is nodirect current path, and the receiver is simply inoperative until the supply conductors are reversed. By shifting the connection of the negative output conductor 5 from the anode al to the supply conductor 3, it is ensured that there is only one direct current path through the tube between the supply conductors. i

The second difiiculty arising if C, Fig. 2, is

' shorted out to produce a direct current path, that of excessive voltage drop in the speaker field when the source of current is direct, is overcome by eliminating the voltage drop due to the section $1 of inductance S when the receiver is to be used with a direct current source. If the inductance S were simply a filter choke, this could be effected by shunting out thissection but, as in the particular arrangements shown, section 31 is part of the speaker field, this is not feasible because the excitation would be too low. Instead, the section 81, 'as shown in Fig. 3 is connected across the output conductors so that part of the excitation of the speaker field is due to current which traverses the section s in returning from the external or receiver circuit,-and part is due to current directly through s1. The only voltage drop, insofar as the external circuit is concerned, is that due to the section s, and the output voltage is suitably high for satisfactory operation.

Referring again to Fig. 1, the system there shown has the advantage that the user of "the set need not know before hand whether the available power source is alternating or direct, and if direct, what the poling may be. The switching system is not only simple, but foolproof, in that, insofar as damage to the apparatus is con cerned, the position of switch 1 is of no consequence and the set may be plugged into an alternating current or a direct current line of either polarity. If the switch 1 is in the alternating current position and there is no sound from the loud speaker when the supply conductors are connected to line LL, it follows that the source is of direct current and accordingly the switch 1 is thrown to the direct current side; set is still silent, the supply conductors 2, 3 are reversed to obtain proper poling. If the switch is in the direct current position and the reproduction is weak and accompanied by loud hum, the switch is thrown to the AC position. At the same time that the connections between'the output conductors and the rectifier circuit are changed, the speaker field sections are properly connected to obtain suitable output voltage.

While I have illustrated a preferred arrangement, it is to be understood that my invention is not limited thereto but is co-extensive in scope with the appended claims.

What I claim is:

1. A system for supplying anode current from and if the a source of alternating current or a sourceof .di-

rect current comprising a full-wave rectifier having two pairs of unlike elements, condensers connected in series between unlike elements of sep-' arate pairs of said rectifier, input conductors connected respectively condensers and to other unlike elements of said rectifier, and switching means for connecting output conductors across said condensers in series for voltage doubling when said input conductors are connected to an alternating current source, and alternatively for connecting said output conductors to said point and'to one of said first rectifier elements when said input conductors are connected to a source of direct current.

2. A system for supplying anode current from a source of alternating current or a source of direct current comprising a full-wave rectifier having two pairs of unlike elements, condensers connected series between unlike elements of separate pairs of said rectifier, input conductors connected respectively to a point between said condensers and to other unlike elements of said rectifier, output conductors, an impedance having substantial resistance, and switching means for connecting said output conductors across said condensers in series for voltage doubling whensaid input conductors are connected to an alternating current source, and simultaneously to connect said impedance in one of said output conductors to produce a substantial drop of the output voltage, and alternatively for connecting said output conductors to said point and to one of said first rectifier elements when said input conductors are connected to a source of direct current, and

simultaneously to reduce the drop of output voltage efiected by said impedance.

3. A system for supplying anode current from a source of alternating current or a source of direct current comprising a full-wave rectifier having two pairs of unlike elements, condensers connected in series between unlike elements of separate pairs ofsaid rectifier, input conductors connected respectively to a point between said condensers and to other unlike'elements of said rectifier, output conductors, a speaker field winding having substantial resistance, and switching means for connecting said output conductors across said condensers in series for voltage doubling when the input conductorsare connected to an alternating current source and simultaneously connecting said field winding in series with one of said output conductors, and alternatively for connecting said output conductors to said point and to one of said first rectifier elements when said input conductors are connected to a source .of direct current, and simultaneously to connect said field winding between said output conductors.

4. A system radio apparatus from a source of alternating current or a source of direct current comprising a full-wave rectifier having two pairs of unlike elements, condensers connected in series between unlike elements of separate pairs, of said rectifier, input conductors connected respectively to a-point between said condensers and to other unlike elements of said rectifier, output conductors one of which is connected to one of said first pair of rectifier elements, and switching means for connecting another output conductor to said point for operation from a direct current source, or to the other of said first rectifier elements for operation from an alternating current source.

5. A system to a point between said for supplying anode current for for supplying anode current for rent or a source of d rect current rectifier her 5 two or uni scents, condensers connected series lost-ween unlike elements of separate of said rectifier, input conductors connected respectireis? between ssid con J d h merits seid rec" wl-iicii is cause elements, a means i? one of iirst rectifier switching source, nu Y ously wili ing scid. sp

tcpe was for inciuds conductors ductcrs when current.

6. A system to rcdio apparatus sin rent or a source of direct 2 g e, fuil=wave rectifier hfifiiillg' two pairs of unlike ele- Inents, condensers connected in ser es between unlilieelements pairs said rectifier, input conductors connected respectively to a point between said condensers and to other unlike elements of said rectifier, output conductors one of which is conne to one of said first rectifier elements, a divide speaker field winding, switch= ing means for connecting another output conductor to said point for operation from a direct current source, or to the other of said first rectifl er elements :Eor operation from an alternating duster connected to the cathode element or a current source, and switching means operable simultaneously with said first switching means for including said speaker field in the negative output conductor when the source of supply is alternating current, and for transferring of the speaker field winding between sci-d output conductors when the source of supply is direct current.

-7. A system for supplying anode current for radio apparatus from a source of alternating current or a source oi direct current comprising a full-Wave rectifier leaving two pairs of unlike elements, condoers connected in series between unlike elements or separate pairs of said rectifier, input conductors connected respectively to at point between said condensers and to other "wire of said rectifier, a positive output con met rectifier'elements, a speaker field winding, and switching means for connecting said windin lietwcen the anode elements of said first rectiilc e einents and the negative output terminal o e ere operation when the source oi sup l alternating current, and for connecting pa i, oi the speaker field winding between said poi s end. 1e positive output conductor and another p t of said field winding between said point t'ne 2??"til6 output terminal for operation when so vroe of supply is direct current.

A system for supplying" current to; radio apparatus from a source of alternating current or a source of direct current comprisin a i'ull wave rectifier having two pairs of 1:11 elements, an input conductor connected to un rectifier elements of separate pairs, condensers connected in series between other unlike rectifier elements, a second input conductor connected between said condensers, an output conductor connected to one of said second named rectifier elements, and switching means for connecting the other output conductor to said second supply ecu cluster for operation when the source is direct cur rent, and for connecting it to the other or said second named rectifier elements when the source is alternating current.

9. A system for supplying anode current for radio apparatus from a source of alternating current or a source of direct current comprising a low impedance rectifier having two anodes and two cathodes, a supply conductor connected to one of said anodes and-one of said cathodes, a filter system, condensers connected in series between the other or" said anodes and the other of said cathodes, a supply conductor connected to a point between said condensers, and switching means manually operable to one position to connect the input conductors of said filter system across said condei sers in series to effect voltage doubling if said. source is alternating current and to prevent injury to the rectifier if said source supplies direct current, and operable to another position to connect said filter input conductors across one of said condensers to provide a direct current path through the rectifier if said source is of direct current and properly poled, and to prevent injury to the rectifier if the source direct current. 

